In a vast dwarven empire beneath the mountains, the lowest of the low are the Rescues: orphans raised as second-class citizens, forever indebted to the society that claims to have saved them.

Eden, a human Rescue and gifted mapmaker, wants nothing more than to pass his exams, keep his head down, and endure. But when a black dragon attacks and his friend Anya faces an unjust trial, Eden, Anya, and their elven companion Faras are forced to flee, bound for the imperial capital.

Hoping to disappear, they discover instead that the empire is not what it seems. Armies are marching. Dark creatures are stirring in the deep. And in the shadows, a secret eighty years old is waiting to rewrite everything about their world.